Perforated belt evaporative cooler



Feb. 5, 1957 A. TEPLlTZ PERFORATED BELT EVAPORATIVE COOLER Filed Feb. 5, 1954 FIELE- f: I i I v 192067222 l J 44590 75 1/72, WWW

United States Patent PERFORATED BELT EVAPORATIVE COOLER Alfred Teplitz, Pittsburgh, Pa., assignor to United States Steel Corporation, a corporation of New Jersey Application February 5, 1954, Serial No. 408,530

2 Claims. (Cl. 62-439) This invention relates to a perforated belt evaporative cooler and more particularly to such a cooler which can be used in air conditioning units or in industrial cooling equipment. Air conditioning units are comparatively expensive and are of such complexity that it requires a skilled mechanic to repair them. Spray ponds, cooling towers and the like are often used for industrial cooling, but they are comparatively expensive and require spray piping, pump, nozzles, etc. which often become clogged.

It is therefore an object of my invention to provide a perforated belt evaporative cooler which is inexpensive, simple in construction and which is easily maintained.

This and other objects will be more apparent after referring to the following specification and attached drawings, in which:

Figure 1 is a vertical sectional view of the cooler of my invention;

Figure 2 is a fragmentary view of the top part of the cooler taken at right angles to Figure 1;

Figure 3 is a view, similar to Figure 2, showing a modification; and I Figure 4 is a view showing a slight modification.

Referring more particularly to the drawings, the reference numeral 2 indicates a self-centering roll arranged with its axis substantially horizontal. The particular roll shown is of the type disclosed in the patent to Lorig No. 2,592,581, dated April 15, 1952. Other self-centering rolls, such as those disclosed in the patents to Lorig Nos. 2,593,157 and 2,593,158, dated April 15, 1952 may also be used. Each of these types of rolls includes a pair of axially opposed substantially identical roll sections having the diameter of their adjacent ends at least as large as the diameter of the rest of the section, and means for causing each section to rotate at the same angular velocity as the other with the peripheries of the sections being so arranged with respect to each other that forces exerted on the object being moved have components on the object engaging surface of each section directed axially toward the adjacent ends of the sections. The roll 2 is provided with shaft sections 4 extending from the body of the roll and supported in bearings 6. 'A shaft extension 8 is provided at one end of the shaft for connection to a motor 9 which may be operated by gas, oil, gasoline, electricity, etc. An endless belt 12 passes around the roll 2 and extends downwardly into liquid L, such as water, in a tank 14. The belt 12 may be made of various types of material such as double woven wire belting, porous fabric or the like. The weave should be balanced and it is absolutely necessary that the material have a plurality of openings therethrough. In other words, it must be perforated so that there will be openings in which the liquid is entrained. If desired the roll 2 may be full-bodied, that is, have a width as great as or greater than the width of the belt or narrow-bodied as shown in Figure 3, that is, have a width less than the width of the belt. In some instances the self-centering roll 2 may be replaced by a solid cylindrical narrowbodied roll 2, as shown in Figure 3. While not as posi- "ice tive in its action as the self-centering roll 2, the roll 2' will cause the belt 12 to remain centered on the pulley due to the following action. When the belt 12 is displaced from the center an unbalanced deflection a' of the unsupported horizontal portion of the belt occurs. This causes the belt edge E-E to curve inwardly as shown in Figure 3. An element of strip A-A moving toward the roll, parallel to the roll axis will arrive at the roll nearer to a centered position than any element preceding it such as B-B. Thus the loop moves toward a central posi tion on the pulley until the unbalanced deflection disappears, and remain centered thereafter. In case it is desired to have a greater length of the belt in the liquid L a snubber roll 16 may be provided adjacent the bottom of the belt. A fan 18 is preferably arranged adjacent the belt 12 and is driven by a motor 20. Where natural air currents can be utilized the fan can be omitted. An outlet 22 is provided at the bottom of the tank 14 leading to a heat exchanger 24. A circulating pump 26 is preferably installed in conduit 28 leading back to the tank 14. The heat exchanger 24 includes a coil 30 having fins there n and a motor driven fan 32 for blowing air thereover. In other instances, such as shown in Figure 4, the coil 30 may be enclosed in a container 34 through which liquid to be cooled passes.

In operation the roll 2 is rotated at a low peripheral speed such as 10 to 50 feet per minute. As the belt 12 passes through the liquid L in the .tank 14 the liquid passes into the openings therein and is carried upwardly with the belt. The air passing through the belt 12 will evaporate part of the liquid L, thus cooling the air and the liquid remaining on the belt. The speed of the belt 12 is so regulated that no substantial amount of the liquid will be thrown therefrom as it passes around the roll 2 and so that a substantial amount of the liquid will remain on the belt as it returns to the tank 14. This speed will depend somewhat on the type of liquid L being cooled and the structure of the belt 12. The correct rate of speed can readily be determined by observation. The air and liquid L are rapidly cooled to the dewpoint of the air by blowing air through the belt. The cooled air can be utilized for cooling purposes where its relatively high humidity is not objectionable. The cooled liquid L returned to the tank 14 cools the liquid remaining in the tank. Of course the liquid can never be cooled to a temperature less than the dewpoint of the air. The cooled liquid passes from the tank 14 through conduit 22 to the heat exchanger 24. In the case of air conditioning the fan 32 blows air over the coils 30, thus cooling the air and delivering it to the room to be cooled. The liquid L picks up heat from the air and is returned to the tank 14 for further cooling. In this case the roll 2, belt 12, container 14 and associated mechanism will preferably be located outside the building or room being cooled. When the cooler is used to cool a processing liquid the operation is the same except that the processing liquid is passed through the container 34 over the coils 30. The belt 12 is subjected to external forces which tend to throw it sideways off the roll 2 or 2', but these forces are resisted by the centering force of the rolls, thus maintaining the belt substantially in centered position.

While several embodiments of my invention have been shown and described it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

1. Cooling apparatus comprising a roll arranged with its axis substantially horizontal, means for rotating said roll, a liquid container, an endless belt passing around said roll and suspended therefrom with its lower end extending into the liquid in said container, said belt having a plurality of openings therethrough, said roll rotating a) at a suflieiently low speed to permit liquid to remain on said belt until it returns to said container, said roll having a substantially cylindrical belt supporting'surface of less width than the Width of said belt whereby the belt extends over both ends of the roll, the unsupported edges.

of said belt deflecting radially of the rollyviththe deflection being greater at either edge that is displaced eff center of the roll thereby causing the belt to move back on center, means for directing a fl-ow of air against said moving belt, a heat exchanger, means for circulating liquid from said container through said heat exchanger, and means for delivering a fluid to be cooled to said heat exchanger.

2. Cooling apparatus according to claim 1 in which the rollis a self-centering roll.

References Cited in the file ofthis patent UNITED STATES PATENTS Martin Aug. 4, 1931 OTHER REFERENCES LorigAligner, p. 10, Figure 6, published by United States Steel, 1953. 

